Insights from Nigerian Research in Ogbomoso
In many parts of the world, turning on a tap and getting clean water is anything but guaranteed. Nowhere is this challenge more pressing than in Nigeria, where water scarcity has become a daily reality for millions. As conventional water sources dwindle or become contaminated, people are increasingly looking to the skies for solutions.
Rainwater harvesting—the simple practice of collecting and storing rainfall—has emerged as a critical strategy for survival. But one question remains: how safe is this ancient practice in the modern world?
Researchers in Southwest Nigeria decided to find out. In a comprehensive study conducted in Ogbomoso, scientists investigated how different storage methods affect the quality of harvested rainwater. Their findings reveal crucial insights that could help millions harness rainwater more safely 3 . As one researcher notes, communicating such scientific work in accessible ways is essential for it to benefit society 1 .
Over 60 million Nigerians lack access to basic drinking water services, making alternative sources like rainwater critical for daily survival.
How water looks and feels—its temperature, clarity (turbidity), and solid content
What's dissolved in the water—including minerals, metals, and nutrients
What microorganisms live in the water—particularly bacteria that could cause disease
The concern with stored rainwater isn't just about what falls from the sky—it's about what happens after the rain lands on your roof and enters your storage container. Contaminants can leach from storage materials, while microorganisms can multiply over time, turning what seemed like clean water into a potential health hazard 5 .
Nigeria's water crisis has been decades in the making. With growing populations, uneven distribution of precipitation, and inadequate infrastructure, alternative water sources aren't just convenient—they're essential. Rainwater harvesting offers a promising solution, particularly because it can be implemented at the household level with relatively simple technology 5 .
Researchers collected rainwater samples and stored them in three different materials commonly used in Nigerian households: metal drums, plastic drums, and traditional earthen pots 5 .
The water was stored for varying periods—one day (D1), five days (D5), and ten days (D10)—to simulate typical household usage patterns 3 .
| Storage Material | Storage Durations | Key Parameters Tested |
|---|---|---|
| Metal drum | 1, 5, and 10 days | Physical: Temperature, Total Solids |
| Plastic drum | 1, 5, and 10 days | Chemical: Nitrate, Nitrite, Electrical Conductivity |
| Earthen pot | 1, 5, and 10 days | Microbiological: Total Coliform |
The researchers organized their results to clearly show how each storage condition affected water quality. The data revealed several important patterns that can guide household water storage decisions.
| Quality Parameter | Metal Drum | Plastic Drum | Earthen Pot | Significance Level |
|---|---|---|---|---|
| Temperature | Moderate effect | Least effect | Greatest effect | Not significant |
| Electrical Conductivity | Moderate | Low | High | Significant |
| Total Solids | Moderate | Low | High | Significant |
| Total Coliform | Moderate increase | Lowest increase | Highest increase | Significant |
Showed the most significant influence on quality parameters, particularly increasing electrical conductivity and total solids 5 . The porous nature likely allowed more contaminant introduction.
Presented a middle ground, though there were concerns about potential metal leaching over time, which could affect chemical parameters 3 .
While storage duration had a more limited impact than expected, researchers noted important trends:
These findings suggest that while rainwater doesn't immediately become unsafe, shorter storage periods are generally better for maintaining water quality.
The most concerning finding related to bacterial contamination. Total coliform levels—a key indicator of potentially harmful bacteria—increased with storage time across all materials 3 . This trend highlights the importance of either using rainwater quickly or implementing simple disinfection methods before drinking stored rainwater, especially after extended storage periods.
| Research Tool | Primary Function | Specific Application in Rainwater Study |
|---|---|---|
| Extech multimeter | Measures physico-chemical parameters | Used to measure pH, electrical conductivity, total dissolved solids, and salinity 7 |
| Nitric acid | Preservation of samples | Added to water samples intended for metal analysis to prevent precipitation and absorption 3 |
| Membrane filtration apparatus | Microbiological analysis | Used with specific culture media to detect and quantify total coliform and E. coli bacteria 7 |
| ICP-MS (Inductively Coupled Plasma Mass Spectrometer) | Trace metal detection | Highly sensitive instrument capable of detecting metals like lead, arsenic, and cadmium at very low concentrations 7 |
| Turbidity meter | Measures water clarity | Quantified the cloudiness of water samples, which can indicate particulate contamination 7 |
The Ogbomoso study fits into a broader scientific conversation about rainwater safety. Research from South Africa has also examined how different roofing materials affect harvested rainwater, finding that while trace metal levels were generally compliant with standards, microbial contamination remained a concern 7 . Similarly, a 2025 study from Soku Community, Nigeria, examined how industrial activities like gas flaring affect rainwater quality, highlighting the role of atmospheric pollution .
As the Ogbomoso researchers concluded, "Care must be taken when storing rainwater to prevent the introduction of foreign contaminants while proper handling must be ensured" 3 .
The Ogbomoso study transforms rainwater harvesting from a game of chance to a science-based practice. By understanding how storage materials and duration affect water quality, households can make informed decisions that maximize safety. While the research confirms that no storage method is perfect, it also demonstrates that simple adjustments—like choosing plastic containers and minimizing storage time—can significantly improve water quality.
As climate change intensifies water scarcity worldwide, harnessing rainwater safely will become increasingly crucial. Research like the Ogbomoso study provides the evidence needed to transform this ancient practice into a reliable modern solution. The message is clear: with the right knowledge, the water from our roofs can quench our thirst without compromising our health.